Could cannibal Hannibal Lecter be capable of empathy? Psychopaths do have empathy, researchers say, but it doesn't come naturally.

A brain-imaging study of 18 violent, psychopathic criminals in the Netherlands, the largest such study undertaken, suggests they can summon empathy when prompted.

The report, published Wednesday in the journal Brain, showed that empathic circuits that are unconsciously activated in the brains of normal people may be dormant or switched off in psychopaths -- not absent, as commonly thought. Those circuits, the study showed, can be activated after psychopaths are prompted to see a situation from someone else’s point of view.

“They do have empathy; it’s just that it’s not always on,” said neuroscientist Christian Keysers of the Netherlands Institute for Neuroscience, lead author of the study, undertaken in Groningen, Netherlands.

Keysers and his team were given access to offenders who committed violent crimes, such as rape and murder, but who were found not responsible due to a psychopathy diagnosis. The offenders are housed in forensic psychiatric facilities, which are obligated to make them available for clinical study.

Each of the diagnosed psychopaths was connected to a functional magnetic resonance imaging machine while he watched video segments showing two hands approaching each other and either caressing, hitting, pushing away or touching the other in a neutral fashion. They were not told what the experiment was about.

The imagery showed that frontal lobe circuits associated with vicarious experience were not activated nearly as much as were those of a control group.

At a second viewing, however, a researcher asked each to put himself in the point of view of one of the actors’ hands. The empathy circuits became more active.

Working with psychopaths is never easy, and rehabilitation that occurs in a psychiatric facility frequently fails in the outside world. Psychopaths are known for adroit social skills that allow them to manipulate people for nefarious ends.

“I don’t think they were manipulating their brain waves to give us what we wanted, which is what they do do when you give them a questionnaire,” Keysers said. “The simple reason is that during the first run when they just watched the movies, we didn’t give them any instruction and they didn’t have any empathy.”

Public fascination with psychopathy has been consistently high, driven in large part by horror movies, novels and pop-psychology treatments. But peer-reviewed academic studies also have linked psychopathic tendencies with the charming, manipulative, grandiose, risky and seemingly guiltless behavior of many leaders, such as politicians, chief executive officers and other telegenic public figures. A 2010 study of 204 corporate professionals found that about 4% met the clinical threshold for psychopathy based on their scores on a psychopathy checklist developed by Dr. Robert Hare at the University of British Columbia.

Theories of psychopathy’s origins center around deficits in instrumental learning and attention. Keyser’s conclusions merge with those hypotheses. Of particular note were scans that showed abnormal activation in the amygdala, an area of the paralimbic system associated with emotional learning. Psychopaths may lack clues to the salience of social stimuli, an attribute shared to a certain degree with autism spectrum disorder. Psychopaths therefore may not be able to develop more complex structures of rules and morals, said Keysers.

“They don’t have this tendency that we normally have to be drawn into what the other person is feeling, and you can rephrase that as an attentional deficit,” Keysers said. “They simply don’t attend to what is going on with other people, automatically.”

Kent Kiehl, a neuroscientist at the University of New Mexico who has amassed the largest collection of brain data on criminals, said other evidence supports Keysers’ conclusions.

“I agree with the paper's thesis that psychopathy is associated with a general lack of responsivity in the paralimbic system, but with effort, attention, manipulation and treatment, we believe psychopaths can increase activity in these regions,” said Kiehl, who was not involved in the Dutch study. “The big question is whether their ability to increase empathy can be regulated in such a manner that they use it in the real world to improve outcomes.”

But there is a substantial gulf between automatic empathic responses and those that result from cognitive control. Because a psychopath likely cannot be "trained" to summon up empathy to counterbalance manipulative and violent behavior, therapies would have to focus on embedding the process where it belongs: in the largely unconscious emotional regulating centers of the brain.

“From a therapeutical point of view, the big implication of our study is it does not seem to be the case that they have broken empathy per se,” Keysers said. “That would suggest that what therapies need to do is not so much try to create empathy in them, but try to make empathy more automatic and potentially do so by making the social cues of others more salient, so they will always be drawn into this empathy mode that they can activate when they want to.”

In that case, Hannibal Lecter might feel a pang of empathy for the frightened, fleeing Dr. Frederick Chilton, his psychiatric hospital tormentor. Or he might have him for dinner.

A brain scan, top, taken when psychopaths viewed film clips, showed little activity in empathy circuits. After being instructed to associate with one of the actors, empathy circuits became more active, as shown in the bottom image.

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